The subject invention relates generally to an improved powder paint collection apparatus for use with a production powder paint application booth.
The application of powder paint has become an increasingly utilized method of painting mass production products, such as automobiles, to reduce the amount of volatile organic compound emissions from a production paint facility. A typical powder paint booth includes a powder paint reclamation system that increases the paint use efficiency upwards of 95%. This type of reclamation system includes a reclamation collector positioned beneath each zone of the paint both. Each zone will generally include several discrete collectors positioned along the length of the zone.
A sectional view of a typical powder application booth is generally shown at 10 in FIG. 1. Each reclamation collector 12 generally includes three sections. A lower section 14 functions as a hopper and collects powder paint funneled into the reclamation collector 12 to be returned the powder reclamation feed system (not shown) as is known to those of skill in the art of powder painting. A filter section 16 is disposed above the lower section 14 and includes a plurality of air filters 18 that are fluidly connected to an air return plenum 20, which returns air to an air inlet plenum (not shown) ultimately to create a downward draft of air inside the powder paint booth.
Each of the prior art reclamation collectors 12 includes a separate air chamber 22 that rises from the filter section 16 to a porous floor 24 of the paint booth 10. Funnel walls 26 expand upwardly and outwardly from the filter section 16 and terminate at the porous floor 24 to collect powder paint particles and air from the entire surface of the porous floor 24 and funnel the particles and air into the lower section 14 and the filter section 16.
While the prior art reclamation collector design has proven somewhat adequate, it has also demonstrated many drawbacks. The separate funnel like air chambers 22 create areas of inconsistent pressure of air circulated through the plenum that disrupts the airflow throughout the booth. A consistent downward draft of air is critical to the paint quality of the product being painted in the booth. Inconsistency in the air pressure within the booth results in inconsistent paint coverage and other paint defects that require repairs to be made to the product. Further, the prior art reclamation collector design results in dead zones both in the reclamation collector and in the paint booth. Dead zones result in accumulations of particulate paint and other dirt that ultimately result in dirt type defects in the product being painted.
Therefore, it would be desirable to provide a reclamation collector apparatus that does not have design dimensions that adversely affect the flow of air through the paint booth. A reclamation collector apparatus that does not adversely affect the flow of air through the paint booth would both improve the efficiency of the paint process by increasing the amount of paint recycled and reduce the number of paint defects on the product by reducing the potential of dirt type defects on the product.
The present invention is a powder paint reclamation collector that improves the flow of fluidized paint particles through a paint booth and into a reclamation collector. The paint booth includes an air circulation system with an inlet plenum that provides downward draft of air through the paint booth and into a return plenum that receives filtered air from the reclamation collector to be recirculated through the paint booth. A plurality of discrete powder reclamation collectors are aligned in rows beneath a porous floor of an application chamber. Each collector includes an upper inlet receiving air and paint particles from the booth and a lower outlet for reclaiming particles.
A continuous chamber is positioned above each row of reclamation collectors and is defined by having continuous side walls connecting the inlets of the reclamation collectors. The air chamber provides a continuous air plenum replacing the separate air funnels utilized in the prior art reclamation collectors. Air and particulate paint not adhered to the product is collected in each of the air chambers and is directed by the continuous plenum to the plurality of reclamation chambers.
The utilization of a continuous air chamber that connects each of the reclamation collectors solves the problems identified with the prior art reclamation collector design. The inventive air chamber improves the consistency of the air flow velocity and the air pressure down the entire length of the booth. Further, the open design allows powder to distribute more evenly in the collector filters reducing pressure drop that may occur when one air filter becomes plugged with particulate paint at a quicker rate than the other air filters in a given zone. Still further, the air filters may be positioned directly in a line of the air flow from the supply plenum, and do not need to be offset into external containers that are in fluid communication with the return plenum.
By utilizing a side wall that extends longitudinally along the length of the booth, a significant reduction in the amount of steel, and therefore the amount of surface area of steel in the booth, can be achieved. The reduction in surface area of steel reduces the potential for dead zones that may result in the accumulation of particulate paint, which reduces both transfer efficiency of the paint and results in an increased potential for dirt type defects in the paint finish of the product through the agglomeration of paint particles.